Average grid demand for this UK day.
On 21 December 2025, Britain’s electricity grid averaged 33.96 GW of grid demand, with renewables averaging 54.9% of tracked domestic generation and carbon intensity averaging 129 gCO₂/kWh. Daily UK electricity demand, generation, carbon intensity, imports, exports and key records.
Average grid demand for this UK day.
Highest 15-minute grid demand period.
Average carbon intensity where available.
Average renewable share of tracked generation.
Live Grid Data UK
On 21 December 2025, Britain’s electricity grid averaged 33.96 GW of grid demand, with renewables averaging 54.9% of tracked domestic generation and carbon intensity averaging 129 gCO₂/kWh. Daily UK electricity demand, generation, carbon intensity, imports, exports and key records.
Daily insight
On 21 December 2025, Britain’s electricity grid averaged 33.96 GW of grid demand, with renewables averaging 54.9% of tracked domestic generation and carbon intensity averaging 129 gCO₂/kWh.
The highest demand period was 41.33 GW at 17:00, while the lowest carbon intensity period was 71 gCO₂/kWh at 23:30.
Daily chart
Generation mix